Means for suppressing the resistance of the negative-electrode flame in electric vapor apparatus.



P. O. HEWITT; MEANS FOR SUPPRESSING THE RESISTANCE OF THE NEGATIVE ELECTRODE FLAME IN ELECTRIC VAPOR APPARATUS. APPLICATION FILED MAR. 21. 1902.

%%,43%., Patented Apr. 12,1910.

UNITED STATES PATENT OFFICE.

PETER COOPER HEWITT, OF NEW YORK, N. Y., ASSIGNOR, BY MESNE ASSIGNMENTS, TO COOPER HEWITT ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

MEANS FOR SUPPRESSING THE RESISTANCE OF THE NEGATIVE-ELECTRODE FLAME IN ELECTRIC VAPOR APPARATUS.

Specification of Letters Patent.

Patented Apr. 12, 1910.

Application filed March 21, 1 902. Serial No. 99,333.

To all whom it may concern:

Be it known that I, PETER CoorER HEWITT, a citizen of the United States, and a resident of New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Means for Suppressing the Resistance of the Negative-Electrode Flame in Electric Vapor Apparatus, of which the following is a specification.

This invention relates'to improvements in the class of vapor apparatus described and shown in various patents issued to me on the 17th day of September and the 3rd day of December, 1901.

The operation of electric vapor lamps, such'for lnstance, as that type of the Cooper- Hewitt lamp in which mercury is used as the negative electrode, is generally accompanied by the a pearance at the negative electrode of a fl dme which, while being somewhat unstable when the surface of the negative electrode is irregular or subject to alteration, proceeds from the negative electrode in a direction at right angles to the surface at which the current enters the said electrode. By a proper selection of the plane of the negative electrode surface, the

irection which this negative flame shall take, can, accordingly, be predetermined. The investigation of the resistance of a vapor lamp, such as described, shows that when this negative flame takes the direction of the path of the current between the positive and negative electrodes of the lamp, the total resistance of the lamp is considerably greater than when the negative flame puts off at an angle to the current path. The excess in resistance under the conditions first named, may equal or exceed fifteen per cent. of the total resistance. It will be understood that the negative flame referred to is practically useless as a source of-light, for which reason the electro-motive-force required to overcome the resistance occasioned by this flame serves no useful function in the lamp and is not only practically wasted but is detrimental. In order to insure that the energy applied to a lamp of this class shall be utilized in the light-givin portion thereof, without needless waste, provide means whereby the surface of the negative electrode shall be so arranged as to insure the projection of the negative flame outside the path of current through the lamp.

The present invention relates to means for accomplishing that end.

It'is also found that the direction of the negative flame is changed by the action of a magnet or solenoid, the flame tending to lie in and along the lines of force. Where it is desired that the negative flame should be out of a right line to the main path of the current, a magnet or a solenoid may furnish a convenient means for accom lishing this result but the deflection o the flame in this way by a magnet or solenoid has the effect of increasing the resistance of the lamp instead of decreasing it. In gen-- eral it may be said that a wide deflection of the negatlve flame is desirable when produced by mechanical means, and a condition of no deflection is desirable when produced by magnetic means. The effect of the magnetic action is to maintain the flame in a stable condition.

The provisions referred to in the foregoing paragraphs are based upon the fact that the negative flame proceeds substantially at right angles to the entrance plane of the current. Thismeans that the entrance surface of the negative electrode should be out of a plane at right angles to the path of the current, in order to cause a suitable position of the negative flame.

I have illustrated my invention in the accompanying drawings, in which- Figure 1 is a longitudinal section of a mercury vapor lamp showing the negative flame in line with the path of current between the electrodes; Fig. 2 is a similar view of a lamp so constructed as to cause the negative tlameto put off at an angle to the current path; Fig. 3 is a section of the lower part of one of my lamps, illustrating a particular form of ne ative electrode; and Fig. 4 is a longitudina section of a lamp similar to that shown in Fig. 1, combined .with a deflecting electro-magnet.

In the drawings, 1 is a tube or container of glass and 2 and 5 are, respectively, the positive and negative electrodes of my lamp. The electrodes are connected through the walls of the lamp to the respective lead-wires, 7 and 8. In Figs. 1, 2 and 3, the positive electrode is of iron and the negative elecangles from the upper surface of the 'mer cury in the direction of the path of the current between the electrode 2 and the elec- In practice, it is found that the trode 5. surface of-the mercury electrode is subject to more or less distortion at the point where the current enters the electrode, for which reason the surface at that point may not be in a plane at right angles to the main path of the current, so that the negative flame, when the negative electrode consists entirely of mercury, may not always take the direction indicated in Fig. 1. But inasmuch as the negative flame may take the direction indicated in Fig. "1, it is desirable that this should be guarded against, by providing an entering surface for the current which shall alwayslie ina direction other than a right angle from the path of the current. I have found that, while the current appears to enter the negative electrode at a small point on its surface, yet it prefers to enter at a point upon aplane surface rather than at an edge or actual mechanical oint or summit. A suitable formation 0 the negative electrode is illustrated-in Fig. 2 wherein a piece of iron, 6, projects up through the mercury 5 and has perpendicular surfaces at which the current enters. With this construction the negative flame is thrown off nearly or quite at right angles to the path of the current between the electrodes.

Fig. 3 illustrates a modification of the negative electrode, in which a piece, 6, of iron, projectsabove the mercury and is provided with a conical or pyramidal shape, the current entering the iron at an angle other than a right angle to the main path of the current, thus causing a deflection of the negative flame.

As a simple mode of illustrating the deflection of the flame by means of magnetic force, I have shown in Fig. 4, a magnet, 12, outside the enlargement in which the negative electrode surface lies. magnet is to deflect or turn the negative; flame approximately as indicated in the drawing. The magnet'may be a permanent magnet or an electro-magnet supplied from a separate source or in a series or shunt re- The effect of the" lation to the lamp. In another application,

and issued as a'patent on January 19, 1904, Number 749,793, I have shown and described this feature in greater detail and have claimed it as a regulating device. Also in a divisional application Serial Number 123,873, filed September 18, 1902, claims are made upon the horizontal lamp described herein.

It is manifest that this invention would apply equally well to a gas or vapor electric lamp and to a gas or vapor electric apparatus designed for any other use.

In another application Serial Number 5%,671, filed March 11,1910, which is a division of this application, I have made claims involving certain features shown and described herein.

I claim as my invention:

1. .In a vapor electric apparatus, a container of suitable shape and dimensions, a positive and a negative electrode therein, and means for causing the surface of the negative electrode at which the current enters it to lie in a plane at an obliqueangle to the path of the current between the two elecject itself out of the path of the current.

2. In a vapor electric apparatus, a suitable container, a positive and a negative electrode within the same, an enlargement surrounding the exposed surface of the negative electrode, and means for so shaping the surface of the negative electrode as to cause it to present an entering plane for the curat an oblique angle to the direct path of the current between the electrodes.

3. In a gas or vapor apparatus of the character described, a container, a positive electrode, a liquid negative electrode, and a solid electrode extension projecting above the surface of the negative electrode, the surface of the projection forming an oblique angle with reference to the surface of the liquid negative electrode.

Signed at New York in the county of New 'York and State of New York this nineteenth day of March A. D. 1902.

PETER COOPER HEWITT.

Witnesses:

WM. H. CAPEL, GEORGE H. STooKBRmeE.

Serial Number 107,603, filed May 16, 1902,

trodes whereby the flame is caused to prorent traversing the lamp, which plane lies 

